In the current display industry, the liquid crystal display (LCD) has gradually replaced the cathode ray tube (CRT) to become a mainstream product due to its excellent properties of low radiation and low power consumption. The liquid filling method of the conventional liquid crystal display is to suck up the liquid crystal slowly by capillarity, after the upper and lower substrates are assembled. Such liquid filling method is time-consuming and is a waste of liquid crystal. Therefore, a new liquid filling method of one drop fill (ODF) is developed. The one drop fill (ODF) process is to directly drop the liquid crystal onto the lower substrate, and then assemble the upper and lower substrates. This new process greatly reduces the time and the materials for filling the liquid crystal, and thus it is absolutely advantageous to the display panel with super large size.
Please refer to FIG. 1 showing a cross-sectional view of the liquid crystal display formed by the one drop fill (ODF) process according to the prior art. The formed liquid crystal display includes a first substrate 11, a second substrate 13, and a black matrix 14, a scan line metal and a data line metal (not shown) and an active display area 12 enclosed between the first substrate 11 and the second substrate 13, which are attached to each other by a seal 15.
In the one drop fill (ODF) process, the seal 15 is solidified by a UV light. Therefore, the seal 15 has to be completely exposed to the UV light for a better solidification effect. However, the liquid crystal material would be damaged by the UV light, and hence, the liquid crystal in the active display area 12 must be protected by a UV shield during the exposure to UV light. The simplest way is to use the combination of the color resist of the color filter and the black matrix 14 as a UV shield of the active display area 12. Although this way is simple, it has a disadvantage that the seal 15 must be located at the area outside the black matrix 14 so as to be fully exposed to the UV light for solidification. To prevent the seal 15 from being shielded by the black matrix 14 and in view of the alignment error during the manufacturing process, the seal 15 has to be at a distance from the active display area 12, which results in an increase of the frame area 17 including the black matrix 14 and the seal 15. Therefore, the effective utilization area of the substrate for display is reduced, and is not suitable for use in the portable product, such as a notebook, that demands a narrow frame area.
Therefore, the purpose of this invention is to provide a liquid crystal display with a narrow frame area to overcome the drawbacks of prior art.